ISSN 1070-4272, Russian Journal of Applied Chemistry, 2015, Vol. 88, No. 6, pp. 999−1003. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © V.V. Samonin, V.V. Dalidovich, E.A. Spiridonova, A.S. Zotov, M.L. Podvyaznikov, 2015, published in Zhurnal Prikladnoi Khimii, 2015,
Vol. 88, No. 6, pp. 902−906.
AND ION EXCHANGE PROCESSES
Preparation and Properties of Mixed Alkaline
Chemical Sorbent of Carbon Dioxide
V. V. Samonin, V. V. Dalidovich, E. A. Spiridonova, A. S. Zotov, and M. L. Podvyaznikov
St. Petersburg State Technological Institute (Technical University),
Moskovskii pr. 26, St. Petersburg, 190013 Russia
Received June 25, 2015
Abstract—The possibility of preparing a high-efﬁ ciency chemical sorbent consisting of calcium and lithium hy-
droxides was determined. The optimal conditions of mixing these hydroxides to obtain the optimal pore structure
and sorption properties of the sorbent were determined. Under the conditions proposed the protective capacity
of the sorbent at low concentrations was increased to almost 40 L kg
Among the current methods of treatment to remove
, a special place belongs to sorption on non-
regenerable alkaline sorbents .
The main non-regenerable chemical absorbents
(CAs) for carbon dioxide are oxides and hydroxides
of alkali and alkaline-earth metals possessing high
stoichiometric capacity. Calcium and sodium hydroxides
have the highest chemical activity. Compounds of
these elements are incorporated into the composition
of various alkaline absorbents used in a wide range of
technological processes. For example, a chemical lime
absorbent (CLA) produced by the domestic industry
contains 96 wt % of Ca(OH)
and 4 wt % of NaOH.
It is used in wet conditions with the initial humidity of
18.5 ± 2.5 wt %.
is the main component of CLAs, responsible
for their chemisorption activity. NaOH and water are
added to activate the reaction of carbon dioxide with
calcium hydroxide, as CO
absorption with dry Ca(OH)
CAs based on lithium compounds (mostly hydroxide)
are also applied, along with CLAs.
However, CA, though has high stoichiometric
capacity, is toxic, expensive, and its large-scale, large
tonnage production is lacking .
Chemical composition, pore volume, pore size
distribution, humidity, and crystal state of the base
material are the main characteristics of massive chemical
absorbents. Each of the above characteristics affects in a
certain way the sorption properties of CLAs.
Studies to improve the CLA properties are mainly
carried out in two directions: the development of the
pore structure and the creation of the optimal water-
retaining properties of the material. The CLA properties
were varied by the introduction of various additives. For
example, the absorbent CLA-I (impregnated) contains
about 4 wt % KMnO
, in addition to Ca(OH)
NaOH . This product has all properties of CLA and
is suitable absorbent for nitrogen oxides owing to the
presence of KMnO
. With introduction of inorganic
additives the range of components being sorbed was
extended, whereas the stoichiometric capacity with
respect to carbon dioxide was not increased .
Carbon dioxide absorbents based on oxides and
hydroxides of alkali and alkaline-earth metals are
characterized by high stoichiometric capacity with
respect to CO
. However, their kinetic characteristics
and strength are low.
In this study, the possibility of obtaining a mixed
chemical absorbent (MCA), which contains comparable